-
Prospective Students
-
Faculty and Staff
-
Current Students
-
Alumni and Friends
Conventional suture ligation of vascular tissues during surgery is time consuming and skill intensive. Alternative techniques require hemostasis through mechanical clips or sutures, which leave foreign objects in the body and disrupt the procedure through the need to exchange instruments. In recent years, energy-based devices, such as ultrasonic (US) and radiofrequency (RF) electrosurgical based technologies, have been used for rapid and efficient blood vessel ligation. These devices expedite numerous labor-intensive surgical procedures (including lobectomy, nephrectomy, gastric bypass, splenectomy, thyroidectomy, hysterectomy, and colectomy). However, both US and RF devices have limitations, including potential for unacceptably large collateral thermal damage zones, with thermal spread averaging greater than 1 mm. This lack of specificity prevents the use of these devices for delicate surgical procedures performed in confined spaces (such as prostatectomy). These device jaws take a long time to cool down to normal body temperature between successive procedures and may also cause thermal damage to healthy tissue through unintended heat conduction from contact with the device jaws.
A novel alternative method using near-infrared (IR) lasers for vessel ligation may eliminate some of these limitations of conventional energy-based devices. In this study, two real-time optical feedback systems are explored along with transparent jaw designs for sealing and bisection of blood vessels. This thesis begins with an introduction and theory of tissue optics followed by the methods used for the study. It describes the use of tissue autofluorescence as a real time optical feedback system. After that, it details the testing and comparison, both experimentally and computationally, of quartz and sapphire optical materials. These materials are transparent and bio-compatible, intended for use in the optical chamber, a critical component of the laparoscopic device jaw. Then, it describes a simultaneous IR laser vessel sealing and bisection study using a quartz optical chamber suitable for integration into a laparoscopic device, and the feasibility of using the optical signal originating from the therapeutic laser and transmitted through the cut vessel, as a closed-loop, optical feedback system for immediately deactivating the IR laser upon successful vessel bisection. The following part discusses future work followed by the summarization of the main accomplishments of this thesis.
Evaluating the impact of motherhood on a woman’s career is complex. There are interrelated mechanisms resulting in conflicting results. The wage disparity for mothers is noted within the literature to range from 0 – 20 percent, with a similar spectrum of negative impact on career progression, when compared with fathers and childless men and women. In this research I summarize the predominant theory-based explanations for the motherhood penalty and review a sample of the research published from 1979 to August 2023. This study shows evidence that a wage penalty for motherhood continues to persist ranging from 14 percent to 32 percent. From the NLSY97 sample of working women (2004-2021), there is evidence of a wage boost for married mothers, women who choose to delay fertility into their late 20s may experience a wage boost, race and a woman’s level of grittiness have no significant impact on women’s wages, and human capital considerations continue to matter and may work to attenuate any wage penalty for motherhood.
In linear dynamics, bounded linear operators over infinite-dimensional Banach spaces have been shown to be able to exhibit interesting characteristics including topological transitivity, topological mixing, and even chaos in the sense of Devaney. This dissertation will examine weighted l^p sequence spaces together with the shift action as the operator. In the case the shift action is over the semi-group N, the above topological properties have been previously characterized by conditions on the weight sequence associated with a given weighted l^p space. This work will present recent results for new characterizations of these properties when the group action over a countable group is instead considered. Additionally, an example choice of the weight sequence in this setting will be presented which yields points which are periodic while having an infinite orbit.
Lastly, new implications for infinite and 0 topological entropy for the weighted l^p space with the shift action over N will be given. In particular, when the weight sequence is summable over a subset of N with positive upper density then infinite entropy may be achieved. Furthermore, when an arbitrary ratio of the weights is bounded above then 0 entropy is guaranteed.
ABSTRACT
CHRISTINE SISK. Effectiveness of Cardiac ERAS Multimodal Analgesia on Perioperative Pain in Adult Cardiac Surgery Patients. (Under the direction of Dr. KATHLEEN JORDAN)
Cardiac surgeries often rely on opioid analgesics, which can lead to adverse effects. The implementation of the multimodal analgesic approach, as a part of the ERAS protocol, has the potential to optimize intra- and postoperative pain management, leading to reduced opioid-related complications and improved patient outcomes. The purpose of this study was to evaluate the efficacy of multimodal analgesia within a Cardiac Enhanced Recovery After Surgery (ERAS) program in reducing postoperative pain and opioid consumption in adult cardiac surgery patients. This study compared the effects of cardiac ERAS multimodal analgesia against traditional opioid-based analgesia on postoperative pain and opioid consumption during the operation and the initial 24 hours postoperative.
The study was conducted at a level-one trauma center that had recently implemented the ERAS protocol on all cardiac surgical patients. Data was collected retrospectively from patients undergoing cardiac surgeries before and after the protocol’s implementation. The pre-ERAS group received traditional opioid-based analgesia, while the ERAS group received the ERAS multimodal analgesia protocol.
Data analysis revealed significantly lower intraoperative opioid consumption in the post-ERAS group compared to the pre-ERAS group (U = 1496.00, p = .026, z = -2.30). However, no statistically significant differences were observed in opioid consumption between the groups at 6 hours and 24 hours postoperatively. These findings suggest the ERAS protocol’s effectiveness in reducing intraoperative opioid requirements but limited impact on postoperative opioid consumption within the first 24 hours.
The study demonstrates that cardiac ERAS multimodal analgesia can effectively reduce intraoperative opioid consumption, highlighting its potential as a valuable component of perioperative pain management in cardiac surgery. While the findings did not show a significant reduction in postoperative opioid use, implementing such protocols can still offer benefits for patient care. This includes reducing opioid-related adverse effects and potentially improving patients’ overall recovery. Further research is needed to explore the longer-term impacts of multimodal analgesia on postoperative opioid consumption and patient outcomes in cardiac surgery.
Since initial applications in the latter twentieth century, the field of micro-optics has greatly expanded. Micro-optics now encompasses research in areas such as integrated optics, micro-electromechanical systems (MEMS), quantum technology, sensing, energy harvesting, and metamaterials. In its current stage, dynamically tunable micro-optics are crucial to providing additional processing power without increasing volume. Micro-structured optics comprise a subsection of micro-optics where the optical response is manipulated by some sub-wavelength or wavelength scale structure. One challenge in developing micro-structured optics are restrictions in terms of geometric freedom and extensive development times. As a solution to some of these challenges, rapid prototyping techniques such as two-photon polymerization (TPP) have been employed in the development of complex two- and three-dimensional optics. TPP provides nano-scale feature sizes, resolutions which surpass the diffraction limit of the light source. In search of ways to add additional degrees of tuning in micro-optics, the unique properties of TPP compatible resins can be exploited. In this study, dynamically tunable micro-structured optics are developed by TPP. Being a polymer, the fabricated structures have unique mechanical properties when compared with conventional glass and metal optics. The structures are designed such that their optical response is sensitive to induced mechanical stress or strain. Both sub-wavelength and wavelength-scale micro-structured arrays were investigated for this mechanical tuning. In each case, changes in the structure's geometry due to mechanical stimuli resulted in a change in the optical response. In combination with a MEMS device, the investigated structures could have applications in integrated optics, mechanical sensing and beamsplitting, and tunable bandgap filtering.
The effects of safe sex practice education on knowledge and attitudes among college students. (Under the direction of DR. KATHLEEN JORDAN)
Introduction: Sexual health education is crucial in reducing the burden of STIs among young adults. Comprehensive sexuality education can lead to positive risk reduction outcomes, such as delayed initiation of sex, a decreased number of sexual partners and frequency of sex, and increased use of contraceptives. The purpose of this study was to evaluate the effectiveness of an educational program focused on sexually transmitted infections (STIs) and safe sex practices among college students who are Greek life members. The intervention aimed to enhance the knowledge and attitudes of these students regarding sexual health and promote healthier sexual behaviors. This project is significant as it endeavors to fill the gap in existing literature concerning the effectiveness of sexual health education in college populations who are at heightened risk for STIs.
Design/Methods: The study utilized a pre-post intervention quantitative design. A convenience sample of 23 sorority and fraternity members aged 18-24 participated in the study. The intervention included an educational session focusing on aspects of sexual health, including transmission, screening, prevention of STIs, as well as safe sex practices. Participants were surveyed before and after the educational intervention using the STD Knowledge Questionnaire (STD-KQ).
Results: Of the 55 Greek life members who completed the pre-test, 23 completed the post-test. A paired-sample t-test showed that there was a statistically significant difference in STD-KQ scores pre- and post-intervention, t(22) = 4.51, p < .001, 95%CI [3.36, 9.08]. The average STD-KQ scores significantly increased from 8.65 ± 5.69 pre-intervention to 14.87 ± 5.69 post-intervention, indicating a significant improvement in STI knowledge and attitudes among the participants after the educational program. Additionally, most respondents reported an increased likelihood of using condoms during sexual activity post-intervention. Additionally, the respondents also reported an increased awareness of STDs and safe sex practices.
Discussion:
The findings highlighted the positive impact of targeted sexual health education in a university setting, especially within the Greek life community. These results underscored the need for universities and health educators to prioritize and integrate sexual health education within the curriculum. Lastly, the study also supports adopting a structured, informative approach to improve students’ awareness and practices regarding STI prevention.
Human Capital Theory has been widely used in academic research to explain the factors that affect career attainment and job promotion potential. According to this theory, investing in human capital can improve career prospects. While previous studies have focused on human and social capital to explain leadership growth within organizations, this research takes a new approach by analyzing telecommuting and how psychosocial support, human capital, and social capital influence employees’ perception of career advancement. In this study, psychosocial support refers to trust, emotional support, and building strong social networks. Education and skills represent human capital, while network ties foster a diverse social level of sponsorship for social capital. All three variables played a role in moderating the relationships between gender, work type, and race as a catalyst for career attainment.
The survey results predicted that women who work from home receive more human capital, which strengthens their career advancement opportunities. Additionally, the results imply that people of color face barriers in achieving career advancement, indicating the presence of a glass ceiling. Career-related support, race, and work type significantly predicted career attainment. These effects provide insights into the dynamics of reaching top management positions within the finance industry.
This dissertation is primarily concerned with the subsystem problem for subshifts of finite type (SFTs) on countable amenable groups. Firstly, we demonstrate that an SFT with positive entropy exhibits a ubiquity of subsystems. We prove that for any countable amenable group G, if X is a G-SFT with positive topological entropy h(X) > 0 and Y ⊂ X is a subshift such that h(Y) < h(X), then the entropies of the SFTs Z which satisfy Y ⊂ Z ⊂ X are dense in the interval [h(Y), h(X)]. Secondly, we present an embedding theorem which provides conditions under which a given subshift may be realized as a subsystem of a given SFT. Let G be a countable amenable group with the comparison property. Let X be a strongly aperiodic subshift over G. Let Y be a strongly irreducible shift of finite type over G which has no global period, meaning that the shift action is faithful on Y. If h(X) < h(Y) and Y contains at least one factor of X, then X embeds into Y. Our proofs rely on recent developments in the theory of tilings and quasi-tilings of amenable groups.
Advances in behavioral genetics provide a game-changing paradigm shift in the development of an accurate framework for a more precise marketing segmentation strategy. Genetics can explain most of the systematic variation between individuals, continuity of behavioral and personality traits, as well as 50% of the variance in human traits. Leveraging that all human behaviors are influenced in some way by the individual’s genetic constitution, a theoretical framework is presented for the definition of a new segmentation base called “Genomics Segmentation”. Moreover, we empirically showed the applicability of the new Genomics Segmentation through a K-mean clustering analysis of the alcohol consumption market using 7 different polygenic scores related to personality and cognitive traits. This study increases the predictive power of consumer behavior and marketing segmentation leveraging molecular genetics and 150 years of behavioral genetics replicable findings. It presents for the first time fundamental principles from behavioral genetics to lay the ground for genomics marketing and the transformation of segmentation strategies. It proposes the segmentation of markets through the genetic propensity of consumers. It not only highlights embryonic research in genomics marketing but also shows the practical application of genomics segmentation through the usage of molecular genetics to create clusters and understand consumption patterns of each subset.
Recent scholarly attention has turned towards evaluations of harmful or “dark” leadership traits and behaviors. However, prevailing literature on destructive leaders primarily delves into leader-centric evaluations of traits, antecedents, and consequences, leaving a significant gap in understanding follower-driven perspectives on evaluations of destructive leaders. This study advocates for a second-order meta-analysis (SOMA) to scrutinize the interplay between evaluations of destructive leaders, the nomological network of concepts surrounding such evaluations, and the relative importance of potential predictors of such evaluations. While primary meta-analytic inquiries abound in the field, their findings sometimes present conflicting results, necessitating a secondary meta-analytic exploration encompassing diverse variables, including follower traits and various manifestations of destructive leadership. This dissertation takes stock of the limitations and opportunities in the extant literature. It presents a roadmap for a cleaned-up concept space, which will allow more robust future research by systematically searching through 256 articles and retaining 30 articles for the initial inclusion before additional searches to fill the remaining SOMA effect size estimates in the correlates in matrices for follower and leader individual differences, leadership construct correlates, and potential outcomes of DLB. Although I successfully coded over 37 follower differences, 68 DLB outcomes, and five destructive leadership constructs as correlates, many missing correlates were primarily tied to outcome relationships, demographics, and personality measures. These missing correlates were initially substantial, with over 70% of the meta-analytic correlation matrices bank. Moreover, the selection process prioritized meta-analytic estimates with the largest sample sizes to mitigate random sampling errors, resulting in comprehensive matrices comprising 182 meta-analytic estimates (total k = 10,818 & total sample size (n) = 2,384,935) not including any Metabus.org derived meta-analytic estimates. Some key statistically significant results include a robust model using eleven follower individual differences (i.e., gender, age, race, five-factor personality traits, positive affect, narcissism, trait anger) with R2 = 0.239 and all incremental correlate additions measured by Change in R Squared with p < 0.05 for all predictor additions excluding age and gender variables. Also, the relative weights and regression coefficients supported these findings. Emotional Stability emerged as a dominant predictor across the personality and demographic traits for followers at RW% = 0.46 with a coefficient β = - 0.652, p < 0.001. Additionally, Trait Anger yielded RW% = 0.23 with a coefficient β = - 0.514, p < 0.001. Additionally, this study suggests the most robust leadership construct relationships to destructive leadership, ethical leadership with ρ = - 0.63 (k = 2; n = 8,186), and unethical leadership ρ = 0.58 (k = 3, n = 2,702).
